Within recent years, smoke detectors both of the ionization and photoelectric types, have been recognized as highly advantageous life-saving devices for use in many varied kinds of installations.
These installations may include power sources which supply either alternating-current or direct-current voltages of different amplitudes.
The systems that employ such smoke detector may include optional auxiliary features, such as, central alarm indication of an activated smoke detector, auxiliary trouble circuits located in various parts of a building, and door control apparatus.
In the usual instance there is no defined detector location and mounting arrangement for such devices. In the main, detector location is determined by careful judgment based on engineering evaluations and field tests where possible.
Accordingly, it may be desirable to either flush-mount or surface-mount a particular smoke detector so as to take advantage of the optimum location available and also to provide an aesthetic application of the detector.
Additionally, in the case of an ionization-chamber smoke detector, a universal detector head may be used with a plurality of different detector bases, the detector bases being designed so that they can accommodate various voltages and auxiliary system configuration. With such an arrangement, only a single detector head need be designed and stocked.